The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

A historic freight system that found the true gold rush is in tourism.

See massive fossils that are over 200 million years old in northeastern Arizona.

Limestone caves with spectacular showcase chambers.

The most famous location in China was home to whole dynasties worth of imperial rulers.

Macabre astrological automaton clock dating to the late 1400s.

North America's largest accredited model railroad museum.

The ghostly remains of an accidental sea.

Along a California highway is a kind of Jurassic Park made of metal.

A world-class observatory in the California desert.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

Towering basalt columns, a creation of fire and ice.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

Ancient human, animal, and geometric figures drawn in the earth.

One of the most unusual geological features, recognizable from a dozen hit movies.

Marta Becket's hand-painted theater in the desert.

"Only the devil could play golf here."

Smooth basaltic rocks tell a tale of ancient glacial waterfalls.

Odd outsider art installations surround a Gold Rush-era ghost town.

An abandoned Jazz Age dream home and con man's hideout in Death Valley.

This blowhole is supposedly caused by a trapped monster.